LARGE MEASUREMENT RANGE MECHANICAL COMPARATOR FOR CALIBRATION OF LONG GAUGE BLOCKS

Tanfer Yandayan
Abstract:
A new design of mechanical gauge block comparator for calibration of long gauge blocks is described. The comparator is constructed by modification of a commercially available universal length measuring machine. It is able to compare the different nominal size gauge blocks with its 300 mm measurement range. This has the advantage that a reference metric size gauge block can be used to calibrate the inch size square or rectangular section gauge blocks or vice-versa. Line scale of the length-measuring machine, which is calibrated by a laser interferometer and gauge blocks, is used for the measurement of displacement. Calibration procedure adapted from EAL-G21 guideline is described with the aid of the results. The uncertainty of the measurements is evaluated and the parameters, which has influence on the uncertainty, is described in detail. The successful application of the comparator for calibration of metric or inch gauge blocks in different cross sections up to 500 mm or 20 inch nominal size is presented with the results. The uncertainty of the comparator with k = 2 is U = [ 1502 + 0.5 L)²]1/2 nm, where L is the gauge block length in mm. For instance, U is calculated as 292 nm (k = 2) for 500 mm long gauge block.
Keywords:
Gauge blocks, mechanical comparators
Download:
PWC-2003-TC14-024.pdf
DOI:
-
Event details
Event name:
XVII IMEKO World Congress
Title:

Metrology in the 3rd Millennium

Place:
Dubrovnik, CROATIA
Time:
22 June 2003 - 28 June 2003